“The enemy is ancient, eternal, and forever. Yet they are not without weakness, for they have been put down before and shall be put down again. The power of the Cerulean Sign has not faded over the eons; it has grown. With its power within my soul, I cannot help but prevail against the Elder Evils, and they cannot help but fall against my might.”
—Selsharra Derissor, a keeper of the Cerulean Sign
The Cerulean Sign is an ancient rune of power, created untold eons ago by a race or deity long since vanished. This ancient race or deity clearly opposed the rise of the aberrant elder races, yet its efforts were ultimately a failure. The aberration races prosper, while their ancient adversary is forgotten by time. All that remains is the Cerulean Sign itself and its still-potent power against creatures from outside the realm of sanity.
The power of the Cerulean Sign has drawn together a small group of loyal keepers. These individuals work to keep the knowledge of the Cerulean Sign alive, for without it, the ancient denizens of the far-realm cannot long be opposed. But the Keepers do far more than simply protect the Cerulean Sign. They seek to take the fight to those elder abominations, and to those that have been seduced by their power. Aberration worshiping cults, insane alienists, careless warlocks, these are the enemies of the Keepers of the Cerulean Sign.
You are one of these Keepers. Chosen for your self-reliance, a sensed potential, or out of desperation you have been brought into the fold. You now know that the tendrils of aberrant taint can slip unseen into the minds of the unsuspecting, so you must keep what you know from the eyes and ears of the uninitiated for fear of exposing your plans and secrets to the enemy. These enemies include not only beholder cultists, slavers who sell to the neogi, and thralls of the illithids, but also the aberrations themselves, and their ageless, unknowable, primal masters that lurk beyond the veil of reality.
Although you know that you have brothers in all corners of the world, you understand that secrecy is of the utmost importance. The only Keepers that you actually know of are your immediate comrades and the one who first entrusted you with the Cerulean Sign. You are given brief often cryptic information through a series of contacts that lead you on to your next endeavor. Though you are pointed in the correct direction, exactly how you address each new problem is entirely up to you. That is not to say that you are completely without support, however. Throughout the realms a series of boltholes, safe-houses, and suppliers unknowingly aid your struggle. Though more often than not those who aid you are good people, they have no idea of your true purpose, only that they have been paid appropriately and are expected to lend aid to those who bear the sign.